A buying points calculator settles the old argument about whether a half point is worth paying for. Here’s the usual spot: your team is +2.5 at -110, and the book will sell you +3 at -120. That half point turns every three-point loss into a push. Is that worth 10 cents of juice? It depends entirely on how often your game lands on 3, and the free calculator above runs the numbers.
How the buying points calculator works
Pick whether the half point moves you on to a number (+2.5 to +3, a loss becomes a push) or off it (+3 to +3.5, a push becomes a win). Choose the number and the calculator fills in a rough push rate, or type your own. It assumes the game is otherwise a coin flip and works out the EV both ways.
The break-even push rate is the line to watch. At -110 to -120, moving on to a number needs it to land about 3.8% of the time. Moving off a number needs about 4.4%. If your number lands more often than that, buy.
Which half points are worth it
In the NFL, 3 is the big one: roughly 15% of games are decided by exactly three points, and for a line near 3 your side lands on it something like 9% of the time. That clears the bar at -120 easily. 7 is next, and usually worth it too. After that it falls away fast. 10, 6 and 4 come up around 3% for your side, which doesn’t cover 10 cents of juice, and 14 is even rarer.
Basketball and college football spread their margins more evenly, so there’s rarely a number worth buying onto. Basketball books also tend to charge more per half point.
A half point costs less on the moneyline side of things if you’re teasing anyway: the teaser calculator shows what six points across 3 and 7 are worth. And the vig calculator will tell you exactly how much the extra juice adds to the book’s margin.
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